Candle manufacture



Nov 1,1949. A. FREVNCH 2,486,469

CANDLE MANUFACTURE 4 Filed Oct. '28, 1947 2 Sheets-Sheet 1 w t B k .g V 3; B m Q u 2S n E r3 k 6'1 g N 3-- a q 0 g u IN V EN TOR.

: Augusf French I BYW M -NOV 1, 1949. FRENCH 2,486,469 I CANDLE MANUFACTURE Filed Oct. 28, l947 2 Sheets-Sheet 2 IN VEN TOR.

Augusf F re nch wa dw Patented Nov. 1, 1949 CANDLE MANUFACTURE August French, Hammond, Ind., assignor to Standard Oil Company, Chicago, 111., a corporation of Indiana Application October 28, 19-17, Serial No. 782,517

4 Claims. 18-27) and continuously without producing distortion and irregularity of the taper.

Another object of the invention is to produce dipped candles more rapidly than has been possible heretofore without encountering distortion or warping of the candles. It is also an object of the invention to provide a rack for dipping candles which will hold the candles in perfect alignment to prevent loss of candles as a result of shifting or distortion while dipping or cooling. Other objects of the invention will become apparent from the following description thereof.

In making dipped candles heretofore, it has been the practice to attach a number of wicks to a rack and lower them into a bath of melted wax. The wax for this purpose is usually mainly paraffin, for example 125 to 135 F. melting point parafiin, generally modified with stearic acid, dye, etc. After dipping the wicks, they are withdrawn from the wax and cooled until solidified. In this operation, a certain amount of tangling occurs 7 which must be corrected by the handwork of the operator. After solidifying, the operation is repeated until the desired thickness of the candle body is obtained. This may require about 25 to 30 dips for the ordinary dinner taper. It is' generally customary to build the body of the candle by dipping in wax of one composition and then finish the candle by a final dip in wax of another composition and/or color, the last operation being called a surface dip. The candles, suspended by their wicks, are then removed from the rack, the butts are trimmed and shaped and the finished candles are ready for packing and shipping. Trimming and shaping of the candle butts may be done before the final or surface clip, for the sake of a uniform pleasing appearance.

One difficulty encountered in this process has been that considerable time is required for solidification of the wax after each dip because of the need for dissipating the very substantial amount of heat of crystallization while the wax congeals. Attempts have been made to speed up the cooling operation by blowing a current of cool air over the candles, by air-conditioning, etc., but the resulting irregular cooling produces an undesirable warping of the candles, which largely increases the number of rejected candles, greatly increasing the cost of the process. It has also been suggested heretofore that rapid cooling be effected by immersing the candles in a bath of cool water after each dip, but the adherence of water to the candles has produced unsatisfactory candles because drops of water adhere to the surface and become occluded in the candles between the wax layers, giving them an irregular, displeasing appearance and causing them to burn badly with spluttering.

I have now discovered that this difficulty with water cooling of candles between dips can be successfully overcome if there is added to the water a substance having the effect of reducing the surface tension of the water. For this purpose I prefer to use those substances known as wetting agents, examples being the sulfonated alkyl benzenes and naphthalenes, the sulfuric acid esters of higher alcohols, such as lauryl alcohol, and the long-chain aliphatic sulfonic acids. Generally the alkali metal salts of the above acids are employed, e. g. lithium, sodium or potassium salts. I may also'employ such surface-tension lowering agents as sulfonated castor oil soap andthe fatty acid soaps such as sodium oleate, sodium stearate, etc. Another class of very useful wettin agents for my purpose includes the alkyl sulfosuccinic esters, particularly sodium or potassium dioctyl sulfosuccinic ester. The amounts of wetting agent required for the purpose are very small, usually of the order of .01 to 1%, depending on the particular agent employed. I have found that it is desirable to employ sufficient surface-tension reducing agent to reduce the surface tension below about 40 dynes per centimeter. The interfacial tension between oil and water is even more indicative of the facility with which the water will disappear from the wax surface. I have found that water having a surface tension below about 40 or an interfacial tension below about 10 dynes per centimeter will not produce droplets on the surface of warm wax candles but will flatten out and substantially all leave the candle when the latter is withdrawn from the cooling water bath. Any residual film of water left on the candle almost instantly evaporates and this can be hastened by ventilating with a current of air, if desired, without any hazard of warping as in the case where the candles are soft and insufficiently cooled. The following table shows the eiTect of three common wetting agents on surface and interfacial tension:

30 provided with suitable resistance to regulate the amount of torque, so that the tension on the wick can be closely controlled as it passes thru the cooling bath in pipe 20. In this way all the wick fibers are properly tensioned in the taper before the wax solidifies and holds them in place.

Instead of the cooling pipe 20, I may employ the apparatus shown in Figure 2 in which the wick, impregnated with melted wax from the bath Interfacial Tension with White Surface Tension, Dynes/Gm. Mineral Oil Dimes/Om l W I W I i Concentratiomllltt. Per CEnt'imWateL- 0.00. 0.025 0.05 0.10 0.20v ,.1. "0.0010025 10,. 010 0.20 00 Wetting Agent: 1 1

Alkyl Benzene Sulfonate of Sodium L 72 29.3 28.9 2859 '29. 5 29.6 38.9 2.4 1. 75 1.4 1.8 2.3 Laurel Sulfate of Sodium 72 29.8 27 10. 24 2 -8 38.9 8.4 7.2 5.2 5.0 Lauryl Monoglyceride Sulfate of Sodium 3 l- 72 25.6 24.7 24.4 24.7 38.9 .6 7.4 5.1 5.0

1 Benzene alkyleted with chlorinated kerosene and sulfonated' (Naccanol).

9 Crude lauryl alcohol sulfate (Draft).

3 Coconut fatty acid monoglyceridesuliate (Vel).

The invention is illustrated by drawings which show schematically in Figure 1 an apparatus for impregnating the candlewick with wax in making tapers.

Fi ure 2; is amodifiedeform of cooling .bath, for th wick-treatingioperationishowmin Figure 1; gure 3,; ;shows,;-, an ;,apparatus .for dipping .nd szl an .1 ii-fi u l is a: nd rack ovspe 11des n suitab1e; for ase-with jthe apparatus shownin-Figure Referring itowFigure 1; .a supply. of .candlewick usually; made .-of;braidedicottona is withdrawn fi'f QIIl- SlJOOl. l l, r and;;.passes over sheave. .l 2',down- Award into-the waxi bath 3 ,where it.=pa sses, under s. fi-heaved 4 and thence u-pward over: sheave -I 5, .ex- ,eqess waxebfiing removed r,tromrthe-wickby. passing it thrua hole of suitableqsizedn wiper plate I6.

.: @thery, means for removing ;=excess,,mel ted wax such as doctor blades, etc., may bewemployed, if ggdesined. j "-fI-heswaxjn bath 3:: is .kept..melted at -theldesirecl;-tempfirature bysteamJacket I! while mma eruplw xis. s p i byz t 1;.12he impregnatedawick zat-.;l 9qnext enters the open end [oft ;water+coolingtubelrore channel 2 0. lThe.-0 1 n .-.channe1 120;; pr ferably 7 can bea straight pipe of: sufflcient diameter to permit the passagemf g-the wick ,.-therethru without touching the :.walls. Itshould be ofe sufiicientplength to .;;provide the desired'amount'oi coolin fldependipg 311 hthe e-v ripassa e f :the wick ther thru. Qrdina-rily; about one lto ten; s,ec. nds is. adequate. 1 QOO1il'1g,- waterhis; supplied;( by rrline x2 L. and the -=we a nt-in relatively d lute .soluticmin' sup- .;ply. .tanl 2 2;. is introduced z-by proportioning apump .:;23;a nd- .-line. ,-2 l. tithe-warm waters-is ;discarded.at vweim 25 inte -catch Fbasin-HZG-Leading toa. suitable waste .line. 1; IE1 desired; the waterrmay the .recycled thru; a.cooling pond or other. cooling sys- The treatectwick g0! itaper. -..leaves :the a cooling 1. tube -20,;thru arsuitablaorificeil inzone end and thence passes -;to reel. 2B.:.'where it;-is wound up un-til ready. ior :use. It desired, as cf. of air-may be-caused to. impinge,onthe.wick-.at;2fl..to assist r..ineliminating any water-carried as afilm on the wick. =Orifice. Zlcmay; befla punctured rubber ,jdiaphragmwor other.,.suitable ,elastic packing which will, largely. prevent the .escape. of water i ,from the. cooling tube 20,. altho. little tendency to. escape. is encountered lbecauselof the absence of any appreciable pressure. Reel 28 may be ,--.driven by a dynamometer, or direct current motor,

l3 passes over sheaves 32 and 33, thence downm-ward into cooling water bath 34 where the wick 25 passes under and over pulleys or grooved sheaves 35 .and.-36. These-sheaves.-35and 3fi.lcansberprovided witha lplurality: ofgroovesso .that .the-.wick

- canbe passed over. them aslmany-lti-mesi asidesired in. order; .to- .increase :the rlength= of travel t-beneathsthewater; surface and provide. the relesr -vsired;amount. of cooling time. By: reversing the direction of 1 travel. of. the- .-wick overz sheavesn and. 36, .as-indicated,. all .sidesof ltheiwickcomelin contact -Withmth3 tgroovedsurfaces I and receive a 3 .uniform calendering, giving '\,the cresulting-= wax taper a particularlyhsmooth surfacesu-itablesfor muse. .in wandle. i manufacture. From -.-the-=. cooling ;.bath- 3,4,' .the v wick,. passes. overs sheavea31'iand thence -toreel: 3Baasrhereinaboveedescribed Cool- 4 ll ,ingawatert and wetting agent.- are; supplied. toethe W-bath'-3 l-by lines 39. and-'40;respectivelmthe warm a water overflowing .at 4 I .rvReierring-now to. Figure 3; which illustrates a l machine .for- .-making.dipped-candles. a: suitable '1 At. the .beginning. of,;the1 {operation .thereaisl attached. .to .the .rack by ..numerous clips. or hooks,

not shown a large. Lnumben. of. candlewicksaor mrathertapers cut. to approximately. .theilength l of 50.;the.candles whichitis desired tmmake, forlexaample 82inch; 10inch,"14cinch;--etc.r It-dsmre- .-.-.f.erred :tOfUSE the precoated-wicks .or.-.tapers-.made

-.as-.-j.ust. described; hereinabove. ..-.-II"hewicks hang straight downeand are built up byl-repeatedtap satplications, of. wax ,to..iorm...the...candles Ail-illustrated. Numerous arrangements! .eofi'limachines ..,may be employed .for. ialternatelyl dipping the candles in melted .wax and then coldewater. .con-

.. ttaining, a wetting .agent. .--,-In mnearrangement,

the number oi.wax. b.aths :-.and..water. bathsaare .placedalternately in a circleand alswingingarm suppor.ts.the..cable'l6.and pulleyil ll, so thatpthe a. rack. can .be lowered .manually into the. waxand water. baths..alternately passingarou'nd .the, circle .ui1,til,the candles carewbuilt ,up.i to.' the..desirled thickness. .Theapparatus .Jofith .dralwing shows "only one waxbath 49 which canbemoved to .one

side'uto permit cooling the .caiidlesflby'jdippmg them in water bath .50.

.The, apparatus illustrated is'".fu lly. automatic,

the. power f0r'its operation being"derived from v rotating. gear ,wheel '5 I The wheel .is. ,connected thru crank T52 and connecting armfi53. to the oscillating table '54 upporting'thewater and wax 7 5' baths. By supporting the table on. pivoted le s 55, it is made to remain in' either of two extreme positions for a sufficient time to permit lowering and raising the candle rack into each bath alternately. The positions can be accurately determined by adjustable stops not shown in the drawing. By allowing the crank pin 52 freedom to move in a slot 56 in connecting arms 53, an irregular movement of the table is obtained without altering the constant revolving movement .of the wheel 5|.

container, the crank pin 52 engages the end of slot 55 and sets table 54 in motion, shifting it to the opposite position and bringing the other bath in position below the candle rack. When that has occurred, the gear rack 58 passes out of engagement with the Windlass gear 59, releasing the tension on cable 46. The weight of the candle rack 45 thereuponunwinds the cable from the windless 59, a suitable braking device or shock absorber, not shown, being provided to control the speed of descent of the candles. candle rack is then raised again from the bath by the gear rack 6| engaging windless gear 5.! as hereinabove described. Cool water having its surface tension controlled as hereinabove described by the addition of a wetting agent is supfor maintaining the wax in 49 in melted -condi-- tion can be supplied by a steam coil, a steam jacket, or by electrical heating means supplied by power thru line 64. It is desired to control the temperature of the wax in the dipping bath within rather narrow limits to regulate the deposition of wax on the candles. Ordinarily a bath temperature within the range defined by the melting point of the wax and a temperature about F. thereabove is satisfactory. It is likewise desirable to control the temperatur of the water bath within the range of about 5 F. below the wax melting point down to about F. therebelow. Colder water can be employed to obtain The wax coatin is encountered if too rapid chilling of the wax on the candle is obtained. The lower the temperature of the cooling water employed the thicker the deposit of wax which can be obtained on the following dip in the wax bath. The thickness of the deposit is also increased somewhat by the length of time the candles are allowed to remain in the water bath, inasmuch as more heat is thereby removed from them and a correspondingly greater amount of wax will freeze on the candle surfaces during the next dip.

By employing cooling water containing sufficient surface-tension reducing agent to maintain th surface tension below about dynes per centimeter, the candles are withdrawn from the water bath substantially free from droplets of water and any thin film of water on their sur- .faces is rapidly evaporated before the candles enter the wax bath on the following dip. In order to build up the candle stock from the wick to the finished candle there is usually required '6 only from 10 to 15 clips, owing to the lower temperature attainable with water chilling using wetting agent. In fact, the more efficient cooling obtainable permits two or more wax dips for each water dip, by some modification of the dipping machine. By using the automatic dipping machine just described, hand labor is almost en- .tirely eliminated from the operation until the candles are complete. I also contemplate employing a tensiometer device 65 in cable line 46 which with switch 66 controlling the power to drive wheel 5! automatically stops the opera- ;tion of the machine when the weight of wax .built up on the candles reaches a predetermined amount. A new rack of candle wicks is then substituted by the operator fOr rack and the candles are then finished and removed from the rack as hereinabove described.

Inasmuch as the candles have a lower density than water, I employ guides in the water bath 50 ,to prevent them from tangling and colliding with .each other during the water-cooling operation.

The use of guides, however, requires that the ;candles be spaced on the rack a greater distance placed on the rack and manufactured in a single .cycle of dipping operations. In order to overcome this disadvantage, I may use a rack similar to :that shown in Figure 4 in which the candlewicks are held taut from top to bottom by stringing them in a wire cage. The cage 10, supported by eyelet H, is wound of wire of suflicient stiffness to adequately support the candles and hold them in position. For this purpose, a wire of about #6 to #9 B. & S. gage is generally satisfactory.

Accumulation of wax on the cage is prevented by electrically heating the cage which may be done either by resistance or induction. If the ;resistance method is used the cage is wound of one continuous wire as shown in the drawing, forming a continuous electrical path from one end 12 to the other end 13. Suitable electric connection, not shown, is then made to the ends of the wire and, for convenience, the flexible lead connection may pass upwardly over pulley 41 along with'the cable46. A constant current of electricity may be passed thru the cage during the entire dipping operation or, by means of an automatic switch, the current may be turned on only during the time the cage is in the wax bath or just entering it, thereby heating the wire to sufiicient temperature to prevent wax freezing on the cage beyond a very thin film. Metal wick hooks 14 attached to the cross wires of the cage are provided for stringing the wicks, and considerable operating time is saved by stringing the cage with one continuous wick 15, as indicated in the drawing. The use of water for cooling the dipped candles makes it possible to place the wicks quite close together, just far enough apart so that the finished candles do not touch, as it is not necessary to provide large air spaces between the candles for cooling them.

If induction heating of the candle rack is employed, .it can conveniently be accomplished by an induction coil either surrounding the wax bath, within the wax bath, or above the wax bath. In the latter case, the rack is given a preliminary heating on passing thru the induction coil so that the cage enters the melted wax at a temperature not substantially below the wax temperature, thereby collecting substantially no wax in=the dipping operation, whereas the wicks and candles, being non-conducting, receive no heat from aasegeee 7 the induction coil and enter thewairbath col-d. Asa result, only the candles build up a-"coating of wax during the dipping step. Thewick which passes lateral-1y between the candles,- particularly at the bottom, can be prevented from accumulating wax by passing it beside and in contact with a wire or other'metal conductor connected to the adjoining wick hooks. 'When employing induction heating, the rack is" constructed of metal formed 'to provide a continuous el'e'ctrieal path an'd an electric field-bf 110 to 10-,000-o'Ycles 'canbe used-as is well known, in this art.

While I have described myinvention giving certain specific embodiments thereof, I do'n'o't.

intent; that it be hmited 'thereby-except 'aS -d'escribed in the following claims.

1. The method of making dippea candleswhich comprises alternately dipping a ca'ndle'wiok in a bath ofmelted-parafiin wax' and a bath of cool Water, said water containing a wetting agent in an amount sufiicien'tto reduce the surface tension of the water to *l'ess than about 40 (lyrics per square centimeter, withdrawing the wax-coated ca'ridlewick-from saidwaterof low surfacetension withoutadhering' water droplets and continuing said'alterna't'e dipping in wax and water until said candle is built up to the desired thickness by deposition of wax layers thereon.

2. The methodofclaim 1 wherein said wetting agent is an alkali metal salt of an acid selected I maintaining it under tension, thereby solidifying said'wa'x on said Wick, adding a wetting agent to the water in said bath in an amount suflicient to reduce the surface tension below about 40 dynes per square centimeter, thereby preventing adherence of Water to said wick, and removing said wick from said'water bath.

'4; Inthe methodof making dipped candles "wherein a suitable wick is clipped in a bath 'of melted parafiin wax and then withdrawn to cool the "layer or deposited-Wax and this operation is repeated'until a candle of the desired diameter is obtained, the improvement comprising acceleratin'g the cooling of said 'candle during the period between clips by immersing it in a bath of water maintained at-a temperature below the melting point of the wax, the water in said bath Contain ng a wetting agent to prevent adherence ofwater dropltsto the surface of said candle,

the-amount of said wetting agent being sufiicien't "to reduce the surface tension of the water in said 'bat-h'belowabout 40-d 'ynes per square centimeter.

AUGUST FRENCH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 16,211 McPhetridge Dec. 9, 1856 647,876 Propfe Apr. 17, 1900 725,704 Harvey Apr. 21, 1903 1,960,917 Nagelboort May 29, 1934 1,975,962 Littooy Oct. 9, 1934 OTHER REFERENCES Aerosol Wetting Agents, publication of Americai'1 Cyanamid and'CheInical Corp, New York, N. Y;, 1941, page 66, copy in Div. 49. 

